On Wed, Nov 27, 2024 at 06:03:23PM -0500, Donald Dutile wrote: > The association would be done via the VMM -- no different then what associates > an assigned device to a VM today -- no hw-level (VM-)ID needed; a matter of > exposing > it to the VM, or not; or mapping the (virtual) CMDQ to the mapped/associated > ECMDQ. > They are purposedly mapped 64K apart from each other, enabling page-level > protection, > which I doubt is a per-CPU req for lock contention avoidance > (large-cache-block > spaced would be sufficient, even 4k; it's 64k spaced btwn ECMDQ regs .. the > largest > ARM page size.
There are commands a VM could stuff on the ECMQ that would harm the hypervisor. Without VMID isolation you can't use ECMDQ like this today. Jason
